A Flip of the Switch
by thegirlinthedeathfrisbee
Summary: John and Sherlock wake up one morning to an unexpected change in the both of them. R/R s'il vous plait!
1. Chapter 1

**Author's Note**: Well, hello there reader. This fic is... something. This is a prompt, given by a tumblr user. It was such a fun idea to think about that I decided to go with it. And here's where it gets fun-this is my first Sherlock chapter fic. _Whoa! What! You? Doing a chapter fic_? You may be saying to the screen right now (more likely though, you aren't. Because that's an irrational reaction. Ha.) It won't be a long chapter fic, admittedly, but it will be broken up into chapters.

So for those of you who have been asking me to do something longer: you're welcome and I hope it's up to your tastes.

As always, thanks for reading.

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><p>When John woke that morning, he didn't open his eyes right away. Guilt was pinging around somewhere in his stomach, recanting the previous nights argument with his flatmate. He watched the scene dance across his eyelids-the way Sherlock had shouted, the words that fumbled from his own mouth, the fleeting look of hurt that had made its way into Sherlock's eyes-and he exhaled. Neither of them had been right, of course. Both had said things they probably wouldn't have said had temperaments been cool...<p>

__Slamming doors, raised voices. Sherlock flings his coat off of him, tossing it carelessly over the couch. John is fuming. He's seeing red when looking upon the tall man before him. He too strips out of his coat, but his hands are shaking as he does so. He practically tears the coat off of him, words flying from his mouth.__

__"You couldn't resist, could you? You couldn't help being a dick for just a moment." he says loudly. He's shaking his head, his heart is racing, he's ready for a fight. He's asking for it. "Always out to prove how much more clever you are than everyone around you." he shakes his head. "When, lets face it, in reality you aren't really all that much more clever." __

__Sherlock swings around. His eyes are cold and his face is tight. "As though someone like you is applicable to make such a judgment." he hisses. John glares at him. "Someone like me?" he asks, incredulous. "What do you mean, someone like me?" His hands are balling up into fists, almost instinctively. Sherlock sneers, eyeing John quickly. "Precisely. Someone like you. Someone with no foreseeable extraordinary talents. Another typical peon, comparatively." __

__John's mouth gapes. "A peon? As though you're some sort of God or something?"__

__"Let's face it, John. You've no place to rank my intelligence. Those more intelligent, perhaps. Even those who are equal may take part in deciding where I stand intellectually." His voice is hard and informative. It takes every piece of restraint John has in order to keep from landing a clean punch into Sherlock's supercilious face. "But you? Your opinion of me holds little importance." __

__"Oh, so you think I'm an idiot, is that right? Some kind of blundering imbecile, running about-"__

__"To put it so very eloquently, yes." __

__John laughs a malicious laugh. "At least I know I'm human. I face my fears head on, I feel everything in the world around me. I'm not the one too cowardly to love or hurt or dislike or try." he says. His voice has gone almost giddy. "At least I'm not daft enough to believe I'm above being a human being. You?" he laughs again, and it's one that's filled with pity. "You say you divorce yourself from feeling those things, because it helps your work? No. No, you try to 'divorce' yourself from those things because you're afraid. You're too scared to feel." He shakes his head, a look of something between disgust and pity on his face. "You're a coward. A stupid coward."__

__Sherlock's begun shaking. John's words have struck a chord, he can see it now. It warrants a self-satisfied smirk to cross his lips as Sherlock's cool demeanor falls. "You know NOTHING." Sherlock shouts. "You... you know absolutely nothing of me! Don't for a moment think you've figured me out, Watson." He's shouting. He takes two large strides and he's face to face with John. "You say what suits your needs now, but don't think for a moment you've cracked the code. You are just another person, another stupid human being. Another hindrance." He hisses.__

__"Another hindrance? Is that what I am, another roadblock on your stupid bloody path?"__

__"Did you figure that out all on your own?" __

__John's face comes closer to Sherlock's, so close Sherlock can feel his breath against his face. "You think you've got everyone figured out? You think you've got me figured out?" he growls. "You are the one who knows nothing. You need me."__

__Sherlock backs away. "I don't need you."__

__"Oh, you do Sherlock. You do." John says, shaking his head. "But then again, you'd be too afraid to admit that as well, wouldn't you?"__

__"I DON'T need you!" Sherlock shouts. John doesn't reply as he makes his way from the room. He's done arguing. He refuses to continue on. Sherlock shouts it again. "I DON'T NEED YOU." but John is already making way up the stairs into his room. __

John sighed. He'd have to apologize. He hadn't meant any of the rubbish that had spewed from his mouth. The problem with arguing with people like Sherlock was that they always knew just what to say to throw him over the edge. They knew just the right buttons to push, in just the right sequence, to cause him to be so... he sighed again. Sherlock would surely still be seething. John would have to be the bigger man.

He sat upright finally, heaving a deep breath as he did so. He opened his eyes, momentarily dizzied by the sunlight basking in the room.

Something wasn't right.

His eyes roved the room quickly. He realized what wasn't right about the room. It wasn't _his. _He glanced from the foot of the bed to the dresser. From there, to the wall hangings. The periodic table? No, not his room at all. Sherlock's room. _Sherlock's room? _He panicked. How in the hell had he come to wake in Sherlock's room, in his bed? Sherlock wasn't there, that was for certain. But then... John shut his eyes, rubbing his hands over his head.

That didn't feel right.

His eyes shot open, slowly running his hands over his head once again. He crept his fingers into the hair upon his head, grabbing hold of a lock of hair near the front. He pulled it down before his eyes and revealed the dark strands to himself. "No." he said, but the moment he did so, his hand clasped over his mouth. That wasn't his voice.

"Hello?" he said. Only, he didn't say it. The voice that emitted from his vocal chords was a deep rasp. Not his.

He flipped the comforter from him and stood quickly, striding toward the hook upon which one of Sherlock's dressing gowns hung. He wrapped it around himself, realizing all too suddenly that he was taller. _He_ was _taller_. John had been the same height since he was sixteen. He looked down to the hands that tied the rope around his waist-long, slender fingers. Pale. He sighed, some kind of fear creeping up into his body. What was going on? How could he...? He flung open the frosted glass panel door, stalking into the restroom.

He looked in the mirror, leaning over the sink and staring hard.

He shook his head, shutting his eyes, attempting vaguely to possibly shake the sight from it. That couldn't be right. There was no way. There couldn't be a way.

He opened his eyes and looked to the mirror again.

Blue eyes, light, almost gray in the bathroom's dim lighting. Cupid's bow shaped lips. Sharp, sharp cheekbones, high upon his face. Dark mop of curls atop his head. Pale. Long neck. He stood upright. He turned his head, looking at the profile. "No." he said to his reflection.

It was Sherlock he was staring at. Who was, in fact, staring at him, in the reflection of the mirror before him. John gulped, and so did the reflection of Sherlock. John raised his arm, and so did Sherlock. He could hear the crashing of feet rushing down the stairs, and when he turned his head to look out the open restroom door, Sherlock did the same.

"John!" he heard Sherlock call. Only, it wasn't Sherlock's voice. It was his.

It was even more bizarre to see himself (God, was he _that_ short?) bounding angrily down the hallway into Sherlock's room. He stopped, rounding toward the bathroom door, where John (or was he Sherlock? This was getting confusing.) was standing. He stared at himself. "What... has happened?" Sherlock said. But it was John's voice, coming from John's body. It made John's-the real John's-stomach twist. "I.. I don't know." Sherlock's voice said.

"You've taken my body." John's voice replied.

"How in the hell would I have managed that? I'm not an evil genius and this isn't a fairy tale, Sherlock." John said defensively. The words sounded strange coming out in Sherlock's telltale throaty growl.

Sherlock held his hands up, a signal that asked for silence. "Alright. Alright. Just... just give me a moment." he said. He blinked, inhaling deeply and exhaling slowly. "We're both still ourselves. I'm still in possession of my mind, at any rate. And you obviously still have yours. So then our identities remain. The thing that has changed, however, is our physicality." he looked back up to John. "You seem to have taken on my body, and I have taken on yours."

"We've switched." John replied simply.

Sherlock rolled his eyes dismissively. John wasn't sure he'd ever actually pulled that face while he'd had his body. It was weird, seeing him look like such a know-it-all. Then again, with Sherlock in current possession of his body, it seemed he might be getting to know the face a little better.

Then John had a strange realization.

"Sherlock, I've seen this before." he said. His eyebrows furrowed, his lips parted thoughtfully. He held up a single hand, allowing the thought to sink in. Sherlock stared at him, bewildered. "You've... you've seen this? John, this isn't even medically possible."

"No, no. Not in that way. No." John's eyes widened. "Sherlock, this is from a film."

"A _film?" _Sherlock asked incredulously.

"A film. An older film." The thought was crashing through his mind. He could remember it very vividly-a mother and her daughter not seeing eye-to-eye, a mysterious switch of the bodies, a day lived as one another. He looked back to Sherlock. "Freaky Friday." he said. It was strange to hear Sherlock's voice say the name of such a film.

Sherlock's eyebrows furrowed. His face contorted into disbelief. "Freaky Friday?"

"Yeah, yeah. It's a film. Been done a few times." John said with a laugh. Sherlock's eyebrows furrowed harder-it must have been just as strange to see himself laughing so freely. John shook his head, "Tell me you've seen it."

Sherlock shook his head.

John rolled his eyes, finally stepping from the bathroom. He pushed past Sherlock in a truly Sherlock fashion, making his way into the living room and onto his laptop. As quick as he could, he pulled up information about the movie. Sherlock had followed him, looking over his shoulder. "I can't believe you've never seen this film." John said with a shake of his head. "See, look." he said, pointing. Sherlock leaned over farther, his eyes quickly dashing over the screen. John watched him. It should've confused him more, to find himself in Sherlock's body, watching Sherlock in his, but somehow the initial shock had worn itself off.

Sherlock stood finally, his hands upon his hips. "They have a disagreement and switch bodies until they each have some kind of _revelation _conclusive to one another's thought processes." he said, a note of disinterest in his voice. John turned in his seat, facing Sherlock. "That doesn't ring a bell?"

"I've never seen the film, John."

John rolled his eyes. "No, not what I meant Sherlock."

Sherlock's tongue slid over his teeth thoughtfully, pursing his lips just so. He glanced around the room, eyes dancing quickly over the furniture and the floor and the walls. His coat was still lying across the couch. He turned back to John slowly, his eyebrows raised high. "No." he said.

John quirked an eyebrow.

Sherlock shook his head. "No... it's not scientifically possible." he said slowly. He looked back to the coat on the couch. John knew from the look in his eyes that he was reliving the previous night. His brain was raking over every moment. Then he shook his head again, giving an irritated scoff. "Brilliant. So _you're_ assuming we've been punished for having a row, and won't return to our normal states until we've seen each others perspectives, is that right John?"

"Any better ideas, Sherlock?"

For once, Sherlock had none.


	2. Chapter 2

**Authors Note:** Thank you for your feedback. I'm not sure why I'm leaving a note. I think I just _like _leaving notes. I hope this reads right. You'd tell me if it was starting to get confusing, right? Right? I hope so.

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><p>There has to be a way." Sherlock proclaimed into the quietness that had enveloped them.<p>

"Well, there is."

"Oh, don't John. This isn't a film, this is _reality_, somehow. Though I can't understand how." Sherlock muttered, waving his hand dismissively. John rolled his eyes, sighing as he shut the laptop closed. _Reality?_ They'd just woken up to be in one anothers bodies. How Sherlock could possibly try to figure out a _realistic_ course of action was beyond him. Sherlock was pacing, his hands behind his back and his strides not nearly as long as normal. Though his strides weren't entirely his fault. After all, John's legs were considerably shorter than Sherlock's. John spread his legs out in front of him, smirking. Now it would be he who had to wait for Sherlock. Just the thought cause a small fit of glee.

"John, please stop looking so _pleased._ This is a serious situation." Sherlock said suddenly.

John looked to Sherlock. "My apologies. Lost in thought..." he replied quietly.

Another silence had come over them. Sherlock had continued pacing, his hands now steepling at his mouth. The mannerisms of Sherlock Holmes followed him, no matter which body he seemed to have. And, John noted with just a hint of jealousy, no matter which body he seemed to have, they always looked graceful.

He stood then, re-wrapping the dressing gown around his lean frame once again as he made his way to the window. London was characteristically gray, rain clouds hovering what seemed like just above their heads. He glanced downward, eying the cars that passed down Baker Street. Cabs, luxury cars, not-so-luxurious cars... his eyes stopped on one car—a police car. He watched it as it pulled up the street and made a final park, right in front of Speedy's.

And out from it popped Lestrade.

"Shit." John mumbled, another strange word coming from Sherlock's voice. He turned quickly. "Sherlock, company." he said quickly.

Sherlock dashed to the other window, throwing open the curtains and peering down at the street. He didn't speak, but John saw his eyes widen and his jaw clench. The sound of the doorbell caused both of them to turn toward the door. Then they looked at one another. "What do we do?" John asked. If Lestrade was there, he needed help with a case. As usual, he'd turn to Sherlock. But today was no good, today Sherlock wasn't Sherlock. Today _John _was Sherlock, and John couldn't even begin to make the leaps and bounds that Sherlock did.

He swallowed quietly.

They both listened to the sound of Mrs. Hudson answering the door. They could hear the casual exchange of greetings between the two, and the sound of footsteps coming up the stairs. Sherlock's jaw was still clenched tight. His eyes were fixed on the doorway. John knew that he was attempting to sort out a way to make it work, but his time was limited, and his ideas were few. He rushed over quite suddenly, his voice a quick whisper into John's face. "There's no other solution. You'll have to pretend to be me."

"Be you? How in the hell am I supposed to _be you?_" John hissed.

"Go on, do your best impersonation. However, speak little. Allow me to do the talking."

"But I don't do most of the talking around Lestrade."

"Well, today you will. Now hush, they're at the door."

Sure enough, just as John looked up to the door once again, Mrs. Hudson and Lestrade both took their entrance. Mrs. Hudson instantly went for her normal route of clean-up while Lestrade turned to John. "Sherlock, got a minute?" he asked. Sherlock instinctively wheeled around, awaiting his explanation of the circumstances. John looked down at Sherlock. Both stood silently.

Lestrade's eyebrows furrowed. "Is... that a no?" he asked.

_Click. _The realization popped up once again. "Go on then." John said, attempting—and just very nearly failing—to impersonate Sherlock's easy arrogance. Sherlock turned his head slowly, his face slack of emotion but his eyes more than revealing. John had to suppress the smirk that begged to spread across his face.

Lestrade was staring. His eyes darted between the two men, a vague veil of suspicion covering them, before he spoke. "Erm... right. Well. Three people dead, right at the same time, according to forensics. At the exact same time. Three streets apart, each." he explained. Sherlock's eyebrow quirked, and so John made sure to mimic the look. "All three guns used were identical in every way they possibly could be."

"Any association between the victims?" Sherlock asked immediately.

The DI's semi-confused expression quickly became dumb-founded. He stared at Sherlock, there in John's body, blinking quickly as though attempting to right his vision. "Er... not... not to our knowledge. We're still investigating." he explained slowly.

"Three completely random acts of murder happening simultaneously? No. They've obviously got an association somewhere. Any witnesses? People who perhaps saw said murderers?" Sherlock asked quickly. John's jaw clenched as he subtly stomped over Sherlock's toes. He made a sound of protest, wheeling around to give John a piece of his mind, when he met his own neck. He looked up quickly, into John's face, with eyes widened.

He turned back to Lestrade wordlessly, who looked completely baffled by the entire exchange. For a moment, he simply stood with his jaw hanging. Then he recollected himself, looking between the two men quickly. "Er... yeah. Yeah, got statements from neighbors. All said the same thing. Male, mid-thirties, 'bout 5'10 they'd guess, dark, slicked hair, bit on the thin side, no distinguishing marks. Wore black jeans and a black jumper." he explained. He wasn't sure where to look. He settled on John's face, or—as he would've seen—Sherlock's. "As it happens, each one of the witnesses ended up describing the same man."

Both men were silent. John could see Sherlock's hands fidgeting. He knew, instantly, that Sherlock had a thought, an important one. If only John was able to delve into his head, for just a moment, to consider his thoughts. He took a long, hard moment to think it through.

_Okay so... they all describe the same man. So... then... it can't be the same man, because it's impossible to be in the same place. _He was trying, he was _really _trying to go through the process, something like Sherlock might do. _Could be triplets? A family business of assassins? No, that's crap. John, come on. Think. How would people who hadn't seen the same murderer describe the exact same man? _He took a deep breath. Lestrade was waiting, his eyebrows raised. _Well, hold on then. 5'10, dark hair, thin, no distinguishing marks. Same dress. But that's pretty vague, isn't it? That could be... _"Not the same man." he said suddenly.

Sherlock visibly relaxed.

"What?" Lestrade asked.

John cleared his throat. He would have to speak quickly to be Sherlock. He'd have to have a smooth train of thought, a stream of consciousness. He prepped his words quickly before he spoke, stepping forward. "The description of each murderer is assuredly the same. However, they're vague." he said. "You could look to the street now and catch a man who was of the exact same description. That doesn't necessarily mean you've caught _any _of the men involved."

"...Alright."

"So... so the murderer, well. He probably wasn't actually there. He hires three men, all of which could be described in about the same way." John was failing at the quick deductions in which Sherlock was infamous for, but the thought was there. He glanced at Sherlock. His jaw was clenched, but his eyes were glittering. He gave a small, hardly-noticed nod. He looked back to Lestrade, feeling confident. "Each of the witnesses then give the exact same description, inevitably fooling those investigating into believing that someone could be in the same place at the same time."

"So... we're looking for three guys that fit that description?"

"We'll need to do some checking into the victim's backgrounds. They have to have a connection." John said confidently. Lestrade nodded, glancing between the two men once again before coming back to John. "You don't think it could've just been... I don't know, some kind of coincidence then? We've been checking for a bit. There's nothing we've seen so far."

John blanched. He racked his brain for an answer, one to Sherlock's standards, but it was still only half awake, and still a bit confused on why he was in Sherlock's body, and... Sherlock stepped in then. "Well, I mean, a guy doesn't go through all that work—getting three guys that can be described exactly alike—just for a couple of people on the street." Sherlock suggested.

"Right. So you think there's something we missed?" Lestrade asked.

John, in a truly Sherlock fashion, rolled his eyes. "Obviously." he replied simply.

Lestrade nodded, the bewilderment easing from his face. "So then you'll come round?" he asked.

John sniffed, looking uninterestedly from the detective inspector and glancing out the window. What would Sherlock be thinking at that point? He couldn't be certain. "Leave the address." he said finally. "I'll be round soon." He threw a glance at Lestrade, who nodded as he whipped out the small notebook from his breast pocket. He quickly jotted down the address and tore the page from the book. "Soon, yeah?" he asked.

"Within the hour." John assured him.

Lestrade nodded once more before turning and rushing from the flat. John glanced into the kitchen, making sure that Mrs. Hudson had taken her leave before finally exhaling with relief. His hands were shaking subtly, he realized this as he put them over his eyes. Sherlock released a laugh. John shook his head, giggling. "That wasn't so bad." he said.

"Certainly could've been worse." Sherlock replied, placing his hands over his hips. "However, there is now the problem of a case. We have a case. Or rather, _you _have a case." he went on, glancing up at John.

"I have a case." John repeated. Because he was Sherlock. He was the man with the sharp eyes and the sharper mind, apparently. John sighed then, weary at the thought of attempting to be Sherlock for any longer. "This is insane." he muttered.

"Should've told him you couldn't take it." Sherlock said.

"You wouldn't have said no to Lestrade." John replied.

"I might have. Given the circumstance. Though it is a curious case, three deaths, three identical men, three separate streets. Someone has an affinity for the number three." he said thoughtfully. He strode to the window once again, peering out and down the street. John did the same—both men watched as Lestrade's car finally pulled away from its parking spot and shot off down the street. Sherlock pulled his curtain closed. "Now, John. I'll need your assistance with this next part." he said, making his way toward the staircase.

John furrowed his eyebrows, "For what?"

"Dressing. You'll need to instruct me on an outfit you may put together."

"You couldn't just... guess?"

"The thought had also occurred to me that you may feel..." he paused, thoughtful. "_Uncomfortable, _with my obtaining the knowledge of your body." he said. His voice, John's voice, sounded strange carrying the lofty tone that Sherlock innately held. And for a split second, the idea _was _uncomfortable to John. But he was in the military. Loads of people had seen him down to nothing. But for Sherlock to see... he bit back the discomfort. "No. No, It's fine." John finally replied.

"Is it?" Sherlock asked.

John nodded. "If anything happens to my body, I'll know who did it. That'll be nice and easy."

Sherlock looked him over. Something told John that Sherlock—despite his easy demeanor—was still having difficulty accepting that he wasn't the man before him. Finally, Sherlock looked back to John's eyes. With his chin tilted upward, he turned, stepping upon the first step. "The day's suit is hanging behind the door." he mentioned.

"Right." John replied. He watched as Sherlock ascended the stairs.

"Oh, wait, Sherlock... I just had a thought!" he said suddenly, taking the stairs two at a time to catch up to him. Sherlock stopped, turning just as the two men became face to face. John grabbed hold of the banister as he asked, "Are you... erm, uncomfortable? Me seeing you? Just wondering."

Sherlock's eyes danced around the room momentarily before, finally, he looked back to John. "No. It's acceptable, in the given circumstance." he replied. John nodded, "Right. Just thought I'd ask. Just in case."

"We're both adults. I'm sure we can manage to dress without becoming too fascinated with one another's genitalia." Sherlock mused.

"Right."

"Oh, and we should probably become re-acquainted with our names." he mentioned. John furrowed his eyebrows. Sherlock gave him a knowing look. His voice dropped down to a murmur, "After all, you are Sherlock, and I am John. And if someone were to hear us calling one another by the opposite names, say... Mrs. Hudson? They might ask questions. Ones to which we have no answer."

"Oh... right. Of course." John nodded. He'd have to make sure not to respond to John. Only to Sherlock. Only for now.

"Suits on the hook. Should be the black shirt today." he said as he turned back up the stairs.

"Right." John said absently, making his way back to Sherlock's—_his _room.


End file.
